To investigate associations between sibling weight status, concerns about sibling weight, and parents' differential use of restrictive feeding practices. Participants included 70 mother-father pairs with two biological children between 6 and 12 years old. Each parent completed three Child Feeding Questionnaire (CFQ) subscales (perception of child weight, concern about child weight, and restriction) for each participant sibling. Researchers measured heights and weights and converted child data into Body Mass Index percentiles (BMI%). Multiple regression analysis examined predictors of restrictive feeding practices used by both parents. The nature of differential treatment was examined by calculating Pearson's correlations among sibling differences (older minus younger sibling) in maternal and paternal CFQ reports and sibling BMI%. Concern for child weight, but not actual child BMI% or parental perception of child weight, predicted restrictive feeding practices for both parents. Child gender was not related to child weight status, perception of child weight, concern for child weight, or restriction. Parents were more likely to use differential restrictive feeding practices when they had differential concern for the weight status of their children. However, this differential treatment was not related to differences in actual sibling BMI% or parental perception of child weight. Parental concern for child weight, rather than actual child weight status, predicts restriction by both mothers and fathers. Across families, parents generally tend to use similar feeding practices with each of their children. Within families, parents may have different interactions with each sibling regarding food when differentially concerned about sibling weight status.